Structural member



July 22, 1941. J. E. owm 2,250,253

STRUCTURAL MEMBER Filed March 30, 1939 Z0 I IN VENTOR /4 75%) EBoWey BY 3 gi o/ways.

Patented July 22, 1941 STRUCTURAL MEMBER John E. Bowen,

Detroit, Mich, assignor to Great Lakes Steel Corporation, Ecorse, Mich., a corporation of Delaware Application March 30, 1939, Serial No. 264,997

4 Claims.

The present invention relates to structural members, and in particular, is directed to improvements upon the structure disclosed and claimed in Patent No. 1,900,541, granted March 7, 1933, to H. W. Buelow et al.

The above identified patent discloses and claims a metallic structural member, particularly well adapted for general use in the framing of dwellings or other structures. The structural member is adapted to be formed from relatively thin sheet metal stock, by a suitable die or rolling operation, and as specifically disclosed may be characterized as comprising a pair of channelshaped members arranged with the Webs thereof in back-to-back but spaced relation, so as to form a fastening groove therebetween. The two webs are complementarily corrugated in the direction of their length, so that a nail or other fastening element, upon being driven into the groove transversely of the member, is caused to be bent first in one direction and then in the other direction.

In accordance with the present invention it is found that the structural member may, for certain applications, be generally improved by replacing one of the channel-shaped members with a pair of spaced angle members, one leg of each whereof lies parallel to the corresponding flange of the other channel-shaped member, and the other leg or web portion of each whereof lies in back-to-back relation to, but spaced from, the web of the channel-shaped member. The corrugations are, of course, formed in such web portions of each angle member, and the resultant structural member is characterized as having a single web, as distinguished from the double web specifically disclosed in the above patent. Further, the efficiency of the structural member may be noticeably increased, in its single web form, by forming the corrugations so that they extend inwardly from the inner face of the web of the channel member, thus more advantageously locating the center of gravity of the structural member and increasing the strength of the member against buckling under load.

Both of the above single and double web structural members are preferably formed of relatively light sheet metal, of the order for example of 16 gauge. In the manufacture of these members, it has become customary to subject a fiat strip of the metal to a cold forming operation, so as to reduce it to the channel section, and so as to also introduce the corrugations into the channel section. Due to the lightness of these sections, this cold forming operation inherently introduces a waviness into the resultant channel members, and this waviness materially reduces the ability thereof to withstand buckling stresses. It has been found, in further accordance with the present invention, that the just mentioned waviness may be entirely eliminated from the web of the channel member by providing stiffening ribs, which ribs may be introduced therein as an incident to the cold forming operation. In addition to performing the just mentioned important function of eliminating the waviness from the web, and thereby materially increasing it in strength, the stiffening ribs additionally give column stiffening to the web, in the same Sense that separately applied ribs additionally stiffen conventional structural members, such as plate girders, and the like.

With the above as well as other considerations in view, it will be appreciated that the primary objects of the present invention are to provide a structural member embodying the above generale ly described improvements over the structure described and claimed in the aforesaid patent; to provide such a structure of the single web type, made up of a channel-section member to which a pair of angle members are secured, the angle members and the web of the channel member being deformed to provide nailing groves, which nailing grooves are offset inwardly from the inner face of the channel member; to provide a structural member of the above type which may be economically formed by a die or rolling oper ation, from sheet metal of relatively thin section, and which is extremely efficient; to provide an improved structural member, characterized as embodying stiffening ribs extending transversely of the web; to provide such a structure wherein the stiffening ribs are formed from the metal of the web by a die forming operation or the like; and to provide such a structural member wherein separate flange portions are employed, having a groove between them, which flange portions are connected together at spaced points along the length thereof, and wherein the stiffening ribs are located coincidentally with the connecting means.

With the above as well as other objects in view which appear in the following description and in the appended claims, a preferred but illustrative embodiment of the invention is shown in the accompanying drawing, throughout the several views of which corresponding reference characters are used to designate corresponding parts, and in which:

Figure 1 is a view in perspective of an embodiment of the invention;

Fig. 2 is a view in vertical transverse section,

' taken along the line 2-2 of Fig. 1;

in Fig. 1 is made up of a channel member in, having a web I2 and flanges l4, and a pair of angle members l6. It will be noted that the resultant member is of generally I-section, each composite flange being formed by one leg of the corresponding angle member l6, and by the corresponding flange ll of the channel member Ill. The web I2 is provided with a pair of spaced corrugations 20, each of which preferably extends substantially throughout the length of the structural member, and is positioned immediately adjacent the corresponding flange l4. Each corrugation extends inwardly from the inner face of the web. In addition, the angle members iii are each provided with a longitudinally extending corrugation 22, complementary in form to the corrugation 20.

In order to connect the angle members I6 to the channel member In, the latter is provided with a plurality of bubbles 28, which are indented in the corrugation 20, and which bubbles 28 abut the crest of the corresponding corrugation 22. In order to complete the connection, a spot weld, such as 30, is preferably provided between each bubble 28 and the corresponding corrugation 22'. With this relation, it will be appreciated that what may be called the web portion l6a of each angle member I6 is rigidly connected in slightly spaced but back-to-back relation to the web l2 of the channel member ID. The space between the just mentioned web portion and the web of the channel member constitutes the previous ly mentioned nailing or fastening groove, into which a fastening device, such as the nail 24 (Fig. 2) may be driven, so as to secure a cooperating member such as 26 to the structural member. In being driven into the nailing groove, it will be appreciatedthat the nail 24 is bent first in one direction and then in the other, so that a positive and secure connection is afforded.

It will be appreciated that a load applied to the structural member, through the connected member 26, for example (Fig. 2), is sustained entirely by the single central portion of the web l2 of the member l0, and is distributed between the angle members l6 and the flanges ll of the member ID. The distribution of the load between the angle member l6 and the outer or flange portion of the member l2 depends in large part upon the spacing between the connecting points 30, as will be understood. The feature of formin the corrugations (20-22) so that they extend inwardly from the inner face of the channel course the effect of increasing the over-all load carrying capacity of the structural member.

As previously mentioned, the above channel member I0 is preferably formed from an initially flat strip of sheet metal, by subjecting it to a forming operation, so as to bring it to the form shown in Fig. 5. This operation completely forms the flanges M, as well as the corrugations 20, and may be relied upon, if desired, to form the indentation 28. As also previously mentioned, however, this operation tends, due to the extreme lightness of the metal section employed, to introduce a waviness into the web l2, which materially reduces the strength thereof. In accordance with the present invention, however, this waviness and the consequent weakening effect thereof, are entirely eliminated by introducing the stiffening ribs 32 into the web l2. The ribs 32 are preferably introduced therein by a forming operation undertaken subsequently to the above described forming operation. Preferably also, the ribs 32 are formed to extend inwardly from the inner face of the web l2 of the channel member III. In addition to the stiffening of the member is found in practice to materially inweb which results from the elimination of the waviness therefrom, the ribs 32 also materially stiffen the web by virtue of their column stiffeningeffect. The resultant web construction, accordingly, though being of relatively thin section, is of very substantial strength.

It will be noted that since the connections between the angle member [6 and the channel member II] are made at the weld points 32, the principal load transference between the angle members [6 and the channel member It! occurs at such points. Accordingly, a further feature of the present invention resides in locating the ribs 32 coincidentally with the weld points 30, thus giving the greatest strength to the web portion at the points of load transfer.

Although only a specific embodiment of the invention has been described, it will be appreciated that various modifications in the form, number, and arrangement of parts may be made within the spirit and scope thereof.

What is claimed is:

1. In a metallic structural member, adapted to receive and hold fastening elements, a metallic channel member having a web and flange portions integral with the web and extending laterally from the inner face of the web, a pair of angle members, one leg of each whereof is secured to the outer face of said web but in spaced relation thereto, so as to afford a fastening groove between each said leg and said web, each said leg and the registering portions of said web being complementarily corrugated, said corru-' gations extending in a direction inwardly from the inner face of said web, and said web having a plurality of longitudinally spaced stiffening ribs extending transversely of and raised from the body of said web, each said rib extending throughout the space between the aforesaid corrugations.

2. In a metallic structural member, adapted to receive and hold fastening elements, a metallic channel member having a web and flange portions integral with the web and extending laterally from the inner face of the web, a pair of angle members, one leg of each whereof is secured to the outer face of said web but in spaced relation thereto, so as to afford a fastening tions extending in a direction inwardly from the inner face of said web.

' 3. In a metallic structural member, adapted to receive and. hold fastening elements, a metallic channel member having a web and flange portions integral with and extending laterally from the inner face of the web, a pair of angle members, one leg of each whereof is secured to the outer face of said web but in spaced relation thereto, so as to aflord a fastening groove between each said leg and said web, each said leg and the registering portions of said webbeing complementarily corrugated, said corrugations extending in a direction inwardly from the inner face of said web, the ridge of one corrugation extending towards the valley of the complementary corrugation whereby to form between them a curved groove to receive a fastening element, the width of said groove and the rigidity of the metallic members being such as to cause said fastening element to bend and thereby'be held in position by contact with the sides of said groove when driven thereinto.

4. In a metallic structural member, adapted to receive and hold fastening elements, a metallic channel member having a web and flange portions integral with and extending laterally from the inner face of the web, a pair of angle members, one leg of each whereof is secured to the outer face of said web but in spaced relation thereto, soas to aiford a fastening groove be tween each said leg and said web, each said leg and the registering portions of said web being complementarily corrugated, said corrugations extending in a direction inwardly from the inner face of said web, the ridge of one corrugation extending towards the valley of the complementary corrugation whereby to form between them a curved groove and the rigidity of the metallicmembers being secured together by indenting the corrugations in said channel member at spaced points therealong so that said indentations abut the ridge of the complementary corrugations.

JOHN E. BOWEN. 

